/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.jasonshieh.qrcode;

import java.util.ArrayList;
import java.util.List;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;

import com.google.zxing.ResultPoint;
import com.jasonshieh.qrcode.camera.CameraManager;

/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder rectangle and partial
 * transparency outside it, as well as the laser scanner animation and result points.
 * 
 * @author dswitkin@google.com (Daniel Switkin)
 */
public final class ViewfinderView extends View {

  private static final int[] SCANNER_ALPHA = {0, 64, 128, 192, 255, 192, 128, 64};
  private static final long ANIMATION_DELAY = 0L;
  private static final int CURRENT_POINT_OPACITY = 0xA0;
  private static final int MAX_RESULT_POINTS = 20;
  private static final int POINT_SIZE = 5;
  private static final int EDGE_SIZE = 40;

  private CameraManager cameraManager;
  private final Paint paint;
  private Bitmap resultBitmap;
  private final int maskColor;
  private final int resultColor;
  private final int frameColor;
  private final int laserColor;
  private final int resultPointColor;
  private final int borderColor;
  private int scannerAlpha;
  private List<ResultPoint> possibleResultPoints;
  private List<ResultPoint> lastPossibleResultPoints;
  private int orientation = Configuration.ORIENTATION_LANDSCAPE;
  int position = 0;
  int directSpeed = 4;
  // This constructor is used when the class is built from an XML resource.
  public ViewfinderView(Context context, AttributeSet attrs) {
    super(context, attrs);
    // Initialize these once for performance rather than calling them every time in onDraw().
    paint = new Paint(Paint.ANTI_ALIAS_FLAG);
    Resources resources = getResources();
    maskColor = resources.getColor(R.color.viewfinder_mask);
    resultColor = resources.getColor(R.color.result_view);
    frameColor = resources.getColor(R.color.viewfinder_frame);
    laserColor = resources.getColor(R.color.viewfinder_laser);
    resultPointColor = resources.getColor(R.color.possible_result_points);
    borderColor = resources.getColor(R.color.viewfinder_border);
    scannerAlpha = 0;
    possibleResultPoints = new ArrayList<ResultPoint>(5);
    lastPossibleResultPoints = null;
  }

  public void setCameraManager(CameraManager cameraManager) {
    this.cameraManager = cameraManager;
  }

  @SuppressLint("NewApi")
@Override
protected void onConfigurationChanged(Configuration newConfig) {
	super.onConfigurationChanged(newConfig);
	orientation = newConfig.orientation;
}
  
@SuppressLint("DrawAllocation")
@Override
  public void onDraw(Canvas canvas) {
    Rect frame = cameraManager.getFramingRect();
    if (frame == null) {
      return;
    }
    int height = canvas.getHeight();
    int width = canvas.getWidth();

    // Draw the exterior (i.e. outside the framing rect) darkened
    paint.setColor(resultBitmap != null ? resultColor : maskColor);
    canvas.drawRect(0, 0, width, frame.top, paint);
    canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
    canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
    canvas.drawRect(0, frame.bottom + 1, width, height, paint);
    
    // Draw Borders
    paint.setColor(resultBitmap != null ? resultColor : borderColor);
    canvas.drawRect(frame.left - 5, frame.top - 5, frame.left + 20, frame.top, paint);
    canvas.drawRect(frame.left - 5, frame.top, frame.left, frame.top + 20, paint);
    canvas.drawRect(frame.right - 20, frame.top - 5, frame.right + 5, frame.top, paint);
    canvas.drawRect(frame.right, frame.top, frame.right + 5, frame.top + 20, paint);
    canvas.drawRect(frame.left - 5, frame.bottom - 20, frame.left, frame.bottom, paint);
    canvas.drawRect(frame.left - 5, frame.bottom, frame.left + 20, frame.bottom + 5, paint);
    canvas.drawRect(frame.right, frame.bottom - 20, frame.right + 5, frame.bottom, paint);
    canvas.drawRect(frame.right - 20, frame.bottom, frame.right + 5, frame.bottom + 5, paint);
    
    if (resultBitmap != null) {
      // Draw the opaque result bitmap over the scanning rectangle
      paint.setAlpha(CURRENT_POINT_OPACITY);
      canvas.drawBitmap(resultBitmap, null, frame, paint);
    } else {

      // Draw a two pixel solid black border inside the framing rect
      paint.setColor(frameColor);
      canvas.drawRect(frame.left, frame.top, frame.right + 1, frame.top + 2, paint);
      canvas.drawRect(frame.left, frame.top + 2, frame.left + 2, frame.bottom - 1, paint);
      canvas.drawRect(frame.right - 1, frame.top, frame.right + 1, frame.bottom - 1, paint);
      canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1, frame.bottom + 1, paint);

      // Draw a red "laser scanner" line through the middle to show decoding is active
      paint.setColor(laserColor);
//      paint.setAlpha(SCANNER_ALPHA[scannerAlpha]);
//      scannerAlpha = (scannerAlpha + 1) % SCANNER_ALPHA.length;
      if(position < frame.top){
    	  position = frame.top;
    	  if(position > 0){
    		  directSpeed = - directSpeed;
    	  }
      }
      if(position + directSpeed >= frame.bottom + EDGE_SIZE){
    	  directSpeed = - directSpeed;
      }
      position = (position + directSpeed) % (frame.bottom + EDGE_SIZE + 1);
//      Log.d("TAG", "position" + position);
//      Log.d("TAG", "directSpeed" + directSpeed);
      paint.setColor(resultBitmap != null ? resultColor : laserColor);
      for(int i = 0; i < EDGE_SIZE; i++){
    	  // over top then cancel draw
    	  if(position - 1 - i < frame.top || position - i > frame.bottom){
    		  continue;
    	  }
    	  int alphaBase;
    	  if(directSpeed > 0){
    		  alphaBase = EDGE_SIZE - i;
    	  } else {
    		  alphaBase = i;
    	  }
    	  paint.setAlpha((int)(((alphaBase * 1.0f) / EDGE_SIZE) * EDGE_SIZE) + 80);
    	  canvas.drawRect(frame.left + 2, position - 1 - i, frame.right - 1, position - i, paint);
      }
      
      Rect previewFrame = cameraManager.getFramingRectInPreview();
      float scaleX = frame.width() / (float) previewFrame.width();
      float scaleY = frame.height() / (float) previewFrame.height();

      List<ResultPoint> currentPossible = possibleResultPoints;
      List<ResultPoint> currentLast = lastPossibleResultPoints;
      int frameRight = frame.right;
      int frameTop = frame.top;
      if (currentPossible.isEmpty()) {
        lastPossibleResultPoints = null;
      } else {
        possibleResultPoints = new ArrayList<ResultPoint>(5);
        lastPossibleResultPoints = currentPossible;
        paint.setAlpha(CURRENT_POINT_OPACITY);
        paint.setColor(Color.RED);
        synchronized (currentPossible) {
          for (ResultPoint point : currentPossible) {
            canvas.drawCircle(frameRight - (int) (point.getY() / scaleY),
            		frameTop + (int) (point.getX() / scaleX),
                              POINT_SIZE, paint);
          }
        }
      }
      if (currentLast != null) {
        paint.setAlpha(CURRENT_POINT_OPACITY / 2);
        paint.setColor(Color.RED);
        synchronized (currentLast) {
          float radius = POINT_SIZE / 2.0f;
          for (ResultPoint point : currentLast) {
            canvas.drawCircle(frameRight - (int) (point.getY() / scaleY),
            		frameTop + (int) (point.getX() / scaleX),
                              radius, paint);
          }
        }
      }
      
      // Request another update at the animation interval, but only repaint the laser line,
      // not the entire viewfinder mask.
//      postInvalidateDelayed(ANIMATION_DELAY,
//                            frame.left - POINT_SIZE,
//                            frame.top - POINT_SIZE,
//                            frame.right + POINT_SIZE,
//                            frame.bottom + POINT_SIZE);
      postInvalidate(frame.left - EDGE_SIZE,
                            frame.top - EDGE_SIZE,
                            frame.right + EDGE_SIZE,
                            frame.bottom + EDGE_SIZE);
    }
  }

  public void drawViewfinder() {
    Bitmap resultBitmap = this.resultBitmap;
    this.resultBitmap = null;
    if (resultBitmap != null) {
      resultBitmap.recycle();
    }
    invalidate();
  }

  /**
   * Draw a bitmap with the result points highlighted instead of the live scanning display.
   *
   * @param barcode An image of the decoded barcode.
   */
  public void drawResultBitmap(Bitmap barcode) {
    resultBitmap = barcode;
    invalidate();
  }

  public void addPossibleResultPoint(ResultPoint point) {
    List<ResultPoint> points = possibleResultPoints;
    synchronized (points) {
      points.add(point);
      int size = points.size();
      if (size > MAX_RESULT_POINTS) {
        // trim it
        points.subList(0, size - MAX_RESULT_POINTS / 2).clear();
      }
    }
  }

}
